Controlled Experiments
by smilingsoprano
Summary: Sherlock makes a deduction about John's love life. John takes issue with it. Awkward conversation about sex ensues. T to be safe. Pre-slash, but easily reads as gen.


**Title: **Controlled Experiments

**Author: **smilingsoprano

**Rating: **T for references to sex.

**Pairings: **This is technically pre-slash, so Sherlock/John if you squint, but it can be read as friendship.

**Disclaimer: **None of this belongs to me. If I owned Sherlock, there would be no plot, only character development, and no one wants that.

**Summary: **Sherlock makes a deduction about John's love life. John takes issue with it. Awkward conversation about sex ensues.

**A/N: **This may eventually be part of a longer fic, but it might not ever get finished. No spoilers because it's short and completely lacking in plot. I'm American and this has not been Brit-picked, so please forgive Americanisms or a lack of Britishisms. Reviews are love and shall be loved in return.

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John did his best to be quiet when reentering the flat, but it was a lost cause. He had barely shut the door when Sherlock's voice issued from the next room.

"Did you stop for groceries? We're out of milk again."

John sighed, shrugging off his coat and walking into the living room. "We've had this conversation, Sherlock. You're the one who takes milk with your tea. So you can damn well buy it."

"A logically sound conclusion, were it not for the not-insignificant fact that over the past few months we have established an effective status quo in which purchasing groceries falls under your capable purview. To now deviate from this pattern would only cause confusion and marked decline in the efficiency of the system." Sherlock had not even glanced up from his newspaper during this explanation, but now his eyebrows drew together in a frown of concentration. "Given that we had long since resolved this difference of opinion, however, I gather there exists a different problem. It obviously does not concern me, as we have reached the point in our relationship where you retain no inhibitions about confronting me. As we have had no particularly traumatizing cases of late, neither does the fault rest with our work. Your general reaction to upsetting news stories tends to be sorrow or acceptance; as a war veteran, it takes more personal events to pierce your emotional barrier. You are returning from a night—an entire night—out with Sarah." Finally, he looked away from his reading, catching John's gaze before he could avoid it. Sherlock's piercing grey eyes fixed on him for a moment, then turned to stare straight into the distance, the discomfiting sign that a revelation was coming.

"Ah. I see."

"See what?" John snapped.

Sherlock arched an eyebrow. "You are fretting over the condition of your intimacy with Sarah. To be blunt, the sex is not as good as it used to be, and you are wondering if you should take it as a sign to break things off."

John spluttered for a moment, once again drawing Sherlock's gaze. "That's rubbish! Sarah and I are fine, thank you very much."

"Your reaction begs to differ."

"Oh, please! Like you bloody well know _anything _about sex!"

He had forgotten how utterly unnerving it was to be the one transfixed by Sherlock's deductive stare. The pale, calculating face, the shock of dark, unruly hair, the coldness and detachment so foreign to his youth. He truly looked a sociopath at those moments. The silence stretched to a nearly unbearable point before the corner of Sherlock's mouth quirked upward in a tiny self-congratulating smile.

"I would venture to propose I know more on the subject than you, John."

A pause, and then John snorted. Then he chuckled. The tension dissolved, and he found himself gasping for breath in a combination of relief and amusement. Sherlock remained impassive as John wiped tears of laughter from his eyes.

"Oh, God, Sherlock, that's the biggest lie I've ever heard you tell. You—I mean, you're the least passionate person I've ever met! I'd have trouble believing you've even kissed someone, let alone gone to _bed_ with them."

Sherlock pursed his lips disapprovingly, the way he always did when John's intellect failed to measure up to his impossible standards. "And that is where you are wrong, John. I am very likely the _most _passionate person you have ever met." As though to firmly undermine his point, Sherlock steepled his long fingers together, looking nothing if not analytical. "I am passionate about my work, my science. Deduction, especially in the investigation of death, requires a basic understanding of people, one I understand I lack naturally and thus have attempted to acquire experientially. And, well—" Sherlock gestured expansively, "—the act of sexual intercourse is a very powerful motivational factor for most people. To the end of parsing its more important aspects, I have therefore conducted controlled experiments, discovering everything I believe I am required to know on the subject."

For a few seconds, John could only gape at this maddening, otherworldly man. "I—but—controlled _experiments_? Good God, Sherlock, is that what you think it's about? No, I _refuse_ to believe you could deduce my thoughts and feelings on the subject if your only experience is purely scientific."

Sherlock shrugged, unfolding from his position on the couch and getting to his feet in that sudden, disjointed way of his. "Perhaps not." He turned to face his flatmate, once again smiling. "But I hardly need to _understand_ your emotions to see them written across your face, John. I may have made an educated guess—as is often necessary in the more subtle aspects of deduction, though God knows you are easy enough to read by now—but the moment I did so, I needed look no further than your expression to know I was correct. Besides—" he once again cast his ice-pale gaze over John, that insufferable grin deepening the corners of his mouth "—if the sex was any good, you wouldn't have come when I texted, would you?" With that, he spun on his heel and exited, looking triumphant.

John glanced at the floor, then sighed. "And that's where you're wrong, Sherlock," he murmured.


End file.
